Cook-Medley Hostility Scale (Ho). The Ho scale (Cook & Medley, 1954) is composed of 50 true-false items taken from the MMPI that measures cynicism and mistrust of others and has adequate test -retest reliability, internal consistency, and construct validity (Smith, 1992). It has been shown in a number of large scale prospective studies to be associated with increased risk for CHD (Miller et al., 1996).